My 50 year old husband had a heart stent placed Wednesday after a 90% blockage was found in his main artery. He is taking Lipitor, plavix, metoprolol, 81mg aspirin and Zoloft. He was taking Imdur, but quit 48 hours ago because of a severe headache. The headache has not lessened. None of the treatments we have tried have touched it. What could be causing the headache and what might help with the pain?